Class EMDoublePairProduction

Inheritance Relationships

Base Type

Class Documentation

class EMDoublePairProduction : public Module

Electron double pair production of photons with background photons.

This module simulates electron double pair production of photons with background photons for several photon fields. The secondary electrons from this interaction are optionally created (default = false). The module limits the propagation step size to a fraction of the mean free path (default = 0.1). Thinning is available. A thinning of 0 means that all particles are tracked. For the maximum thinning of 1, only a few representative particles are added to the list of secondaries. Note that for thinning>0 the output must contain the column “weights”, which should be included in the post-processing. The surface is defined to include the nodes of the grid contained within.

Public Functions

EMDoublePairProduction(ref_ptr<PhotonField> photonField, bool haveElectrons = false, double thinning = 0, double limit = 0.1, ref_ptr<Surface> surface = nullptr)

Constructor The object used to load, store and access to the interaction rates of the process is the interactionRates pointer.

Parameters:

  • photonField – target photon field

  • haveElectrons – if true, add secondary electrons as candidates

  • thinning – weighted sampling of secondaries (0: all particles are tracked; 1: maximum thinning)

  • limit – step size limit as fraction of mean free path

  • surface – Grid will be confined to surface->distance(pos)<0, so for example inside a closed surface

void setPhotonField(ref_ptr<PhotonField> photonField)
void setHaveElectrons(bool haveElectrons)
void setLimit(double limit)

Limit the propagation step to a fraction of the mean free path

Parameters:

limit – fraction of the mean free path

void setThinning(double thinning)

Apply thinning with a given thinning factor

Parameters:

thinning – factor of thinning (0: no thinning, 1: maximum thinning)

void setSurface(ref_ptr<Surface> surface)

Apply a surface that confine the position dependent photon field region. The rates are initialized only for distances smaller then 0, so surface->distance(pos)<0

Parameters:

surface – Grid will be confined to surface->distance(pos)<0, so for example inside a closed surface

ref_ptr<Surface> getSurface() const
void setInteractionRates(ref_ptr<InteractionRates> intRates)

set a custom interaction rate With this function you can change the type of interaction rate, if you would for example like to change from a homogeneous to a position dependent interaction rate.

Parameters:

intRates – ref_ptr to a InteractionRates class

ref_ptr<InteractionRates> getInteractionRates() const
void setInteractionTag(std::string tag)

set a custom interaction tag to trace back this interaction

Parameters:

tag – string that will be added to the candidate and output

std::string getInteractionTag() const
void initRate(std::string path)

Loads the interaction rate This function loads the interaction rate from a given file/folder.

Parameters:

path – The name of the file/folder containing the interaction rates

double getRate(double E, const Vector3d &position = Vector3d(0.), double z = 0) const

Get the interaction rate for a given energy, position, and redshift. For now, this function uses a redshift scaling factor for the interaction rate. Future releases will include a more accurate treatment of the redshift evolution of the photon field.

Parameters:

  • E – Energy of the primary particle

  • position – Position of the primary particle

  • z – Redshift of the primary particle

virtual void process(Candidate *candidate) const

Process function This is the main function to work with, it is called during every ModuleList::run step. Derived functions need to override this overload of process!

Parameters:

candidate – Candidate raw pointer

void performInteraction(Candidate *candidate) const
virtual std::string getDescription() const

Returns description, can be overriden by derived class.

void setDescription(const std::string &description)

Sets description, can be used instead of getDescription in derived class

Parameters:

description – Description string

inline void process(ref_ptr<Candidate> candidate) const

Process function Overload for process function to explicitly make a conversion from ref_ptr to a raw pointer

inline size_t addReference() const
inline size_t removeReference() const
inline int removeReferenceNoDelete() const
inline size_t getReferenceCount() const

Protected Attributes

mutable size_t _referenceCount